Haptics is a tactile and force feedback technology that takes advantage of a user's sense of touch by applying haptic feedback effects (i.e., “haptic effects” or “haptic feedback”), such as forces, vibrations, and motions, to the user. Devices, such as mobile devices, touchscreen devices, and personal computers, can be configured to generate haptic effects. In general, calls to embedded hardware capable of generating haptic effects (such as actuators) can be programmed within an operating system (“OS”) of the device. These calls specify which haptic effect to play. For example, when a user interacts with the device using, for example, a button, touchscreen, lever, joystick, wheel, or some other control, the OS of the device can send a play command through control circuitry to the embedded hardware. The embedded hardware then produces the appropriate haptic effect.
Devices can be configured to coordinate the output of user notifications including haptic effects with certain events or alerts, such as receipt of an incoming message and an upcoming meeting reminder. User attention is increasingly divided between a variety of displays such as smartphones and laptops, and even head-mounted displays. However, these displays are typically unaware of each other and often compete for the user's attention. A game console, for example, may try to inform the user that a download is complete while his/her attention is devoted to the news on his/her smartphone. Users commonly receive concurrent and redundant notifications through a variety of devices in their immediate environment, such as an email notification on both a smartphone and a laptop, which may force the user to decide which display to use. This trend is likely to continue as wearable devices such as head-mounted displays and smart watches become more common. Receiving multiple notifications for the same event, however, can be unpleasant and distracting. Further, the device that ultimately manages to attract the user's attention may also not be the most appropriate for a given type of content or event.